Choose the incorrect statement.

• A
  Increase in incident light beyond a point causes the breakdown of chlorophyll and a decrease in photosynthesis.
• B
  $C_3$ plants respond to increased $CO_2$ concentration and saturation is seen only beyond $450 \ \mu L L^{-1}$.
• C
  $C_3$ plants respond to higher $CO_2$ concentration by showing increased rates of photosynthesis.
• D
  $C_4$ plants show saturation at about $360 \ \mu L L^{-1}$.